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                        多线程
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                            <b>0.1.</b>
                        
                        多线程
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                            <b>0.2.</b>
                        
                        pthread
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                            <b>0.3.</b>
                        
                        NSThread
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                            <b>0.3.1.</b>
                        
                        创建线程的方式
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                            <b>0.3.2.</b>
                        
                        NSThread 的 Target
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                            <b>0.3.3.</b>
                        
                        线程状态
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                            <b>0.3.4.</b>
                        
                        线程属性
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                            <b>0.3.5.</b>
                        
                        资源共享
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                            <b>0.3.6.</b>
                        
                        原子属性
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                            <b>0.3.7.</b>
                        
                        线程间通讯
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                            <b>0.4.</b>
                        
                        GCD
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                            <b>0.4.1.</b>
                        
                        同步 &amp; 异步
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                            <b>0.4.2.</b>
                        
                        block
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                            <b>0.4.3.</b>
                        
                        GCD 常用代码
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                            <b>0.4.4.</b>
                        
                        串行队列
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                            <b>0.4.5.</b>
                        
                        并发队列
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                            <b>0.4.6.</b>
                        
                        主队列
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                            <b>0.4.7.</b>
                        
                        同步任务的作用
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                            <b>0.4.8.</b>
                        
                        Barrier 异步
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                            <b>0.4.9.</b>
                        
                        全局队列
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                            <b>0.4.10.</b>
                        
                        延迟操作
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                            <b>0.4.11.</b>
                        
                        一次性执行
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                            <b>0.4.12.</b>
                        
                        调度组
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                            <b>0.5.</b>
                        
                        NSOperation
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                            <b>0.5.1.</b>
                        
                        基本演练
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                            <b>0.5.2.</b>
                        
                        高级演练
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                            <b>0.5.3.</b>
                        
                        与 GCD 的对比
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                            <b>0.5.4.</b>
                        
                        自定义操作
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                            <b>0.6.</b>
                        
                        异步加载图片
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                            <b>0.6.1.</b>
                        
                        搭建界面&amp;数据准备
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                            <b>0.6.2.</b>
                        
                        同步加载图像
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                            <b>0.6.3.</b>
                        
                        异步加载图像
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                            <b>0.6.4.</b>
                        
                        占位图像
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                            <b>0.6.5.</b>
                        
                        MVC
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                            <b>0.6.6.</b>
                        
                        操作缓冲池
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                            <b>0.6.7.</b>
                        
                        图像缓冲池
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                            <b>0.6.8.</b>
                        
                        代码重构
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                            <b>0.6.9.</b>
                        
                        内存警告
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                            <b>0.6.10.</b>
                        
                        黑名单
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                            <b>0.6.11.</b>
                        
                        沙盒缓存
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                            <b>0.6.12.</b>
                        
                        小结
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                            <b>0.6.13.</b>
                        
                        SDWebImage初体验
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                            <b>0.7.</b>
                        
                        仿SDWebImage
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                            <b>0.7.1.</b>
                        
                        下载操作
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                            <b>0.7.2.</b>
                        
                        测试下载操作
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                            <b>0.7.3.</b>
                        
                        下载管理器
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                            <b>0.7.4.</b>
                        
                        自定义 UIImageView
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                            <b>0.8.</b>
                        
                        SDWebImage
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                            <b>0.8.1.</b>
                        
                        第三方框架
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                            <b>0.8.2.</b>
                        
                        位移枚举
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                            <b>0.8.3.</b>
                        
                        NSCache
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                            <b>0.8.4.</b>
                        
                        SDWebImage常见面试题
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                            <b>0.9.</b>
                        
                        runloop
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                            <b>0.10.</b>
                        
                        自动释放池
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        <a href="./" >多线程</a>
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                        <h1 id="%E5%8E%9F%E5%AD%90%E5%B1%9E%E6%80%A7">&#x539F;&#x5B50;&#x5C5E;&#x6027;</h1>
<ul>
<li>&#x539F;&#x5B50;&#x5C5E;&#x6027;&#xFF08;&#x7EBF;&#x7A0B;&#x5B89;&#x5168;&#xFF09;&#xFF0C;&#x662F;&#x9488;&#x5BF9;&#x591A;&#x7EBF;&#x7A0B;&#x8BBE;&#x8BA1;&#x7684;&#xFF0C;&#x662F;&#x9ED8;&#x8BA4;&#x5C5E;&#x6027;</li>
<li>&#x591A;&#x4E2A;&#x7EBF;&#x7A0B;&#x5728;&#x5199;&#x5165;&#x539F;&#x5B50;&#x5C5E;&#x6027;&#x65F6;&#xFF08;&#x8C03;&#x7528; <code>setter</code> &#x65B9;&#x6CD5;&#xFF09;&#xFF0C;&#x80FD;&#x591F;&#x4FDD;&#x8BC1;&#x540C;&#x4E00;&#x65F6;&#x95F4;&#x53EA;&#x6709;&#x4E00;&#x4E2A;&#x7EBF;&#x7A0B;&#x6267;&#x884C;&#x5199;&#x5165;&#x64CD;&#x4F5C;</li>
<li>&#x539F;&#x5B50;&#x5C5E;&#x6027;&#x662F;&#x4E00;&#x79CD;<code>&#x5355;(&#x7EBF;&#x7A0B;)&#x5199;&#x591A;(&#x7EBF;&#x7A0B;)&#x8BFB;</code>&#x7684;&#x591A;&#x7EBF;&#x7A0B;&#x6280;&#x672F;</li>
<li><code>&#x539F;&#x5B50;&#x5C5E;&#x6027;&#x7684;&#x6548;&#x7387;&#x6BD4;&#x4E92;&#x65A5;&#x9501;&#x9AD8;</code>&#xFF0C;&#x4E0D;&#x8FC7;&#x53EF;&#x80FD;&#x4F1A;&#x51FA;&#x73B0;<code>&#x810F;&#x6570;&#x636E;</code></li>
<li>&#x5728;&#x5B9A;&#x4E49;&#x5C5E;&#x6027;&#x65F6;&#xFF0C;&#x5FC5;&#x987B;&#x663E;&#x793A;&#x5730;&#x6307;&#x5B9A; <code>nonatomic</code></li>
</ul>
<h2 id="%E4%BB%A3%E7%A0%81%E6%BC%94%E7%BB%83">&#x4EE3;&#x7801;&#x6F14;&#x7EC3;</h2>
<ul>
<li>&#x5B9A;&#x4E49;&#x5C5E;&#x6027;</li>
</ul>
<pre><code class="lang-objc"><span class="hljs-keyword">@property</span> (<span class="hljs-keyword">nonatomic</span>, <span class="hljs-keyword">strong</span>) <span class="hljs-built_in">NSObject</span> *obj1;
<span class="hljs-keyword">@property</span> (atomic, <span class="hljs-keyword">strong</span>) <span class="hljs-built_in">NSObject</span> *obj2;
<span class="hljs-keyword">@property</span> (<span class="hljs-keyword">nonatomic</span>, <span class="hljs-keyword">strong</span>) <span class="hljs-built_in">NSObject</span> *obj3;
</code></pre>
<ul>
<li>&#x6A21;&#x62DF;&#x539F;&#x5B50;&#x5C5E;&#x6027;</li>
</ul>
<pre><code class="lang-objc"><span class="hljs-keyword">@synthesize</span> obj3 = _obj3;
- (<span class="hljs-keyword">void</span>)setObj3:(<span class="hljs-built_in">NSObject</span> *)obj3 {
    <span class="hljs-keyword">@synchronized</span>(<span class="hljs-keyword">self</span>) {
        _obj3 = obj3;
    }
}

- (<span class="hljs-built_in">NSObject</span> *)obj3 {
    <span class="hljs-keyword">return</span> _obj3;
}

* &#x6027;&#x80FD;&#x6D4B;&#x8BD5;

- (<span class="hljs-keyword">void</span>)touchesBegan:(<span class="hljs-built_in">NSSet</span> *)touches withEvent:(UIEvent *)event {
    <span class="hljs-keyword">int</span> largeNumber = <span class="hljs-number">1000</span> * <span class="hljs-number">10000</span>;

    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;&#x975E;&#x539F;&#x5B50;&#x5C5E;&#x6027;&quot;</span>);
    CFAbsoluteTime start = CFAbsoluteTimeGetCurrent();
    <span class="hljs-keyword">for</span> (<span class="hljs-keyword">int</span> i = <span class="hljs-number">0</span>; i &lt; largeNumber; i++) {
        <span class="hljs-keyword">self</span><span class="hljs-variable">.obj1</span> = [[<span class="hljs-built_in">NSObject</span> alloc] init];
    }
    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;%f&quot;</span>, CFAbsoluteTimeGetCurrent() - start);

    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;&#x539F;&#x5B50;&#x5C5E;&#x6027;&quot;</span>);
    start = CFAbsoluteTimeGetCurrent();
    <span class="hljs-keyword">for</span> (<span class="hljs-keyword">int</span> i = <span class="hljs-number">0</span>; i &lt; largeNumber; i++) {
        <span class="hljs-keyword">self</span><span class="hljs-variable">.obj2</span> = [[<span class="hljs-built_in">NSObject</span> alloc] init];
    }
    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;%f&quot;</span>, CFAbsoluteTimeGetCurrent() - start);

    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;&#x6A21;&#x62DF;&#x539F;&#x5B50;&#x5C5E;&#x6027;&quot;</span>);
    start = CFAbsoluteTimeGetCurrent();
    <span class="hljs-keyword">for</span> (<span class="hljs-keyword">int</span> i = <span class="hljs-number">0</span>; i &lt; largeNumber; i++) {
        <span class="hljs-keyword">self</span><span class="hljs-variable">.obj3</span> = [[<span class="hljs-built_in">NSObject</span> alloc] init];
    }
    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;%f&quot;</span>, CFAbsoluteTimeGetCurrent() - start);
}
</code></pre>
<blockquote>
<p>&#x539F;&#x5B50;&#x5C5E;&#x6027;&#x5185;&#x90E8;&#x7684;&#x9501;&#x662F;<code>&#x81EA;&#x65CB;&#x9501;</code>&#xFF0C;<strong>&#x81EA;&#x65CB;&#x9501;&#x7684;&#x6267;&#x884C;&#x6548;&#x7387;&#x6BD4;&#x4E92;&#x65A5;&#x9501;&#x9AD8;</strong></p>
</blockquote>
<h2 id="%E8%87%AA%E6%97%8B%E9%94%81-%E4%BA%92%E6%96%A5%E9%94%81">&#x81EA;&#x65CB;&#x9501; &amp; &#x4E92;&#x65A5;&#x9501;</h2>
<ul>
<li><p>&#x5171;&#x540C;&#x70B9;</p>
<ul>
<li>&#x90FD;&#x80FD;&#x591F;&#x4FDD;&#x8BC1;&#x540C;&#x4E00;&#x65F6;&#x95F4;&#xFF0C;&#x53EA;&#x6709;&#x4E00;&#x6761;&#x7EBF;&#x7A0B;&#x6267;&#x884C;&#x9501;&#x5B9A;&#x8303;&#x56F4;&#x7684;&#x4EE3;&#x7801;</li>
</ul>
</li>
<li><p>&#x4E0D;&#x540C;&#x70B9;</p>
<ul>
<li><code>&#x4E92;&#x65A5;&#x9501;</code>&#xFF1A;&#x5982;&#x679C;&#x53D1;&#x73B0;&#x6709;&#x5176;&#x4ED6;&#x7EBF;&#x7A0B;&#x6B63;&#x5728;&#x6267;&#x884C;&#x9501;&#x5B9A;&#x7684;&#x4EE3;&#x7801;&#xFF0C;&#x7EBF;&#x7A0B;&#x4F1A;<code>&#x8FDB;&#x5165;&#x4F11;&#x7720;&#x72B6;&#x6001;</code>&#xFF0C;&#x7B49;&#x5F85;&#x5176;&#x4ED6;&#x7EBF;&#x7A0B;&#x6267;&#x884C;&#x5B8C;&#x6BD5;&#xFF0C;&#x6253;&#x5F00;&#x9501;&#x4E4B;&#x540E;&#xFF0C;&#x7EBF;&#x7A0B;&#x4F1A;&#x88AB;<code>&#x5524;&#x9192;</code></li>
<li><code>&#x81EA;&#x65CB;&#x9501;</code>&#xFF1A;&#x5982;&#x679C;&#x53D1;&#x73B0;&#x6709;&#x5176;&#x4ED6;&#x7EBF;&#x7A0B;&#x6B63;&#x5728;&#x6267;&#x884C;&#x9501;&#x5B9A;&#x7684;&#x4EE3;&#x7801;&#xFF0C;&#x7EBF;&#x7A0B;&#x4F1A;&#x4EE5;<code>&#x6B7B;&#x5FAA;&#x73AF;</code>&#x7684;&#x65B9;&#x5F0F;&#xFF0C;&#x4E00;&#x76F4;&#x7B49;&#x5F85;&#x9501;&#x5B9A;&#x4EE3;&#x7801;&#x6267;&#x884C;&#x5B8C;&#x6210;</li>
</ul>
</li>
<li><p>&#x7ED3;&#x8BBA;</p>
<ul>
<li>&#x81EA;&#x65CB;&#x9501;&#x66F4;&#x9002;&#x5408;&#x6267;&#x884C;&#x975E;&#x5E38;&#x77ED;&#x7684;&#x4EE3;&#x7801;</li>
<li>&#x65E0;&#x8BBA;&#x4EC0;&#x4E48;&#x9501;&#xFF0C;&#x90FD;&#x662F;&#x8981;&#x4ED8;&#x51FA;&#x4EE3;&#x4EF7;</li>
</ul>
</li>
</ul>
<h2 id="%E7%BA%BF%E7%A8%8B%E5%AE%89%E5%85%A8">&#x7EBF;&#x7A0B;&#x5B89;&#x5168;</h2>
<ul>
<li>&#x591A;&#x4E2A;&#x7EBF;&#x7A0B;&#x8FDB;&#x884C;&#x8BFB;&#x5199;&#x64CD;&#x4F5C;&#x65F6;&#xFF0C;&#x4ECD;&#x7136;&#x80FD;&#x591F;&#x5F97;&#x5230;&#x6B63;&#x786E;&#x7ED3;&#x679C;&#xFF0C;&#x88AB;&#x79F0;&#x4E3A;&#x7EBF;&#x7A0B;&#x5B89;&#x5168;</li>
<li>&#x8981;&#x5B9E;&#x73B0;&#x7EBF;&#x7A0B;&#x5B89;&#x5168;&#xFF0C;&#x5FC5;&#x987B;&#x8981;&#x7528;&#x5230;<code>&#x9501;</code></li>
<li>&#x4E3A;&#x4E86;&#x5F97;&#x5230;&#x66F4;&#x4F73;&#x7684;&#x7528;&#x6237;&#x4F53;&#x9A8C;&#xFF0C;<code>UIKit &#x4E0D;&#x662F;&#x7EBF;&#x7A0B;&#x5B89;&#x5168;&#x7684;</code></li>
</ul>
<blockquote>
<p>&#x7EA6;&#x5B9A;&#xFF1A;&#x6240;&#x6709;&#x66F4;&#x65B0; UI &#x7684;&#x64CD;&#x4F5C;&#x90FD;&#x5FC5;&#x987B;&#x4E3B;&#x7EBF;&#x7A0B;&#x4E0A;&#x6267;&#x884C;&#xFF01;</p>
</blockquote>
<ul>
<li>&#x56E0;&#x6B64;&#xFF0C;<code>&#x4E3B;&#x7EBF;&#x7A0B;</code>&#x53C8;&#x88AB;&#x79F0;&#x4E3A;<code>UI &#x7EBF;&#x7A0B;</code></li>
</ul>
<h2 id="ios-%E5%BC%80%E5%8F%91%E5%BB%BA%E8%AE%AE">iOS &#x5F00;&#x53D1;&#x5EFA;&#x8BAE;</h2>
<ol>
<li>&#x6240;&#x6709;&#x5C5E;&#x6027;&#x90FD;&#x58F0;&#x660E;&#x4E3A; <code>nonatomic</code></li>
<li>&#x5C3D;&#x91CF;&#x907F;&#x514D;&#x591A;&#x7EBF;&#x7A0B;&#x62A2;&#x593A;&#x540C;&#x4E00;&#x5757;&#x8D44;&#x6E90;</li>
<li>&#x5C3D;&#x91CF;&#x5C06;&#x52A0;&#x9501;&#x3001;&#x8D44;&#x6E90;&#x62A2;&#x593A;&#x7684;&#x4E1A;&#x52A1;&#x903B;&#x8F91;&#x4EA4;&#x7ED9;&#x670D;&#x52A1;&#x5668;&#x7AEF;&#x5904;&#x7406;&#xFF0C;&#x51CF;&#x5C0F;&#x79FB;&#x52A8;&#x5BA2;&#x6237;&#x7AEF;&#x7684;&#x538B;&#x529B;</li>
</ol>

                    
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